Fan



March 4, 1941. J CROOK 2,233,588

FAN

.Filed Aug. 18, 1958 2 Sheets-Sheet 1 J. D. CROOK March 4, 1941'.

FAN

Filed Aug. 18, 1938 2 Sheets-Sheet 2 Patented Mar. 4, 1941 {UNITEDSTATES PATENT OFFICE 15 Claims.

My invention relates to fans and specifically to a simple, inexpensiveand effective means for causing a rotary fan, with its guard and motor,to oscillate or to rotate with reference to its base.

Another object of the invention is to provide ,an oscillatory fan withmeans whereby the length of the oscillations may be adjusted.

Referring to the drawings, which are made a part of this application andin which similar reference characters indicate similar parts:

Figure 1 is a front elevation, illustrating the use of my invention. 7

Figure 2, a side elevation of the same. Figure 3, a section through thefan base, showing the adjustable stroke-limiting means.

Figure 4, a similar view showing another position of the stroke-limitingmeans.

Figure 5, a vertical section showing electrical iconnections, such aspreferably used in connection with a fan mounted for rotation, e. g.,about a vertical axis.

Figure 6, aside view of a modified valve or closure, and; .Figure '7, anelevation of the same.

In the drawings, reference character In indicates the stationary base ofa fan, to which is connected an upper adjustable portion II by means ofa horizontal pivot bolt l2, in well known manner.

and an upwardly extending neck I4.

to the shoulder l3 by means of a flanged collar '18 secured to theshoulder l3 by screws, there being roller bearings l9 interposed betweenflange l1 and co-acting members l3 and I8.

Current is supplied to the motor by means of conductors 20 andv 2|leading to spring-pressed stationary contacts 2223 which engagerespectively with a contact ring and a contact 25. The contact ring 24is connected to aconductor 26 and the contact 25 is connected to aconductor 21, contacts 24 and 25 being mounted in an insulating block 28which rotates or oscillates with the support I6, as the case may be,while contacts 22 and 23 are mounted in an in-- sulating block 29 on theadjustable member H of the base Ill.

The impellerfor air comprises the fan shaft 3| carried by the armatureor motor l5, as usual, and the fan blades 32, These parts and theskeleton or openwork guard may be of any desirable or conventional form.In the present case the guard l'iasfront andrearrings-SB and 34 sup- Thepart II has a shoulder l3 The fan, motor I5 is mountedon a tubularsupport l6 which has at its lower end a flange 11 connected ported byradially extending bars 35 connected to a boss 35' said rings beingconnected by cross bars 36, which may be integral with the radial bars35. In effect these cross bars .act as brackets to support valves now tobe described. 5

For producing an oscillatory movement of the fan without the use of anygears or other complicated and expensive devices I provide valves orclosure members 3'! at opposite sides of the fan, these valves beingshown as consisting of arcuate strips of sheet metal or the like eachprovided at its upper end with hook-shaped ears 38 adapted to be hookedover a suitable support, here shown as consisting of a cross member 36of the guard. At their lower ends these valves have upwardly extendinghooks 39 for engagement with the end portions 40 of an .arcuate yokemember 4 here shown as a wire bent at its middie to provide a downwardlyextending lug or finger 42 projecting from said yoke and having a 0buffer sleeve of rubber or the like, shown at 43. It will be seen thatthe connector 4| maintains the valves 3|31 in a substantially constantspaced relation with reference to each other, such that either valve maybe in contact with the fan guard while the other is substantially spacedtherefrom, as at the right in Figure 1, or both valves may be spacedequally from the fan guard if desired. -It will be noted that crossmember 36 adjacent the lower ends of the valves are also provided withbuffers, preferably in the form of rubber sleeves 44 to deaden the shockwhen struck by a valve 31 and to eliminate noise caused by such shocks.

For limiting the extent of oscillation I provide controlling means, hereshown as consisting in a pair of fingers 45 and 46 pivotally supportedon a projection 41 having a threaded neck 48 and a winged nut 49 thereonfor clamping the fingers in adjusted position. In Figure 3 these fingersare shown as positioned to afford an oscillation over an arc of about90, which is regarded as the normal oscillation. Figure 4 shows thefingers at the limit of their inward movement toward each other, whereno oscillation of the fan is permitted, the valves bein heldequi-distant from the fan at both sides thereof. It will be obvious thatthese fingers may be set .at any point between the wide open position ofFigure 3 and the iullyclosed position of Figure 4. s

The form oibas'e and electrical connections shown in Figure 5 isparticularly adapted for a fan which rotates continuously in onedirection around its base, since-such a construction prevents twistingof the conductor and consequent 2E i i."

breakage. Such a form is, however, also Well suited for use with anoscillatory fan, for similar reasons. When it is desired that the fanshall rotate continuously in one direction the yoke 4| and the controlmembers 45 and 46 may be omitted, as well as one of the valves. In suchcases a single valve such as shown in Figures 6 and '7 is attached toone side of the fan guard and this is preferably not attached pivotallyas in Figure 1 but is formed with lugsil at opposite ends' of the body52 for hooking over a pair of cross members 36 ofthe fan guard.

In the use of a single valve for continuous rotation of the fan thevalve will be attached to one side or the other of the guard, accordingto which direction of bodily rotation is preferred.

If a single valve 52 is attached to the left hand side of the guard inFigure 1', in the manner ,de-' scribed the fan will rotate continuouslto the right in said figure for the reason that theair passes the insideof the valve at greater speed than on the outside of the valve and thepressure of the air on the inside of the valve is less because of suchdifference in air speed; also the air outside the valve is movingforwardly and inwardly thus creating a pressure more than normal on theoutside of the valve. These unequal pressures on the valve cause the fanto oscillate. The nearer the valve is to the tip of the fan blades thefaster will be the rotation as the faster will be the passage of the,air and the greater the reduction of air pressure on the inside of thevalve. If the valve i fixed to the right hand side of the guard theimpeller and guard will rotate bodily (together with the fan motor)toward the left in Figure 1.

If oscillation of the fan is desired two valves are attachedrespectively to opposite sides of the guard as shown in Figure 1,thesevalves being connected pivotally to the cross members of theguardat their upper ends and being secured together at their lower endsby the yoke-like connector 4!. If the impeller be now caused to rotatewith the parts as shown in Figure 1 the entire upper portion of the fanwill move toward the right in said figure until the rubber bufier 43 offinger 42 strikes the control member 46, when the entire yoke 4| will beheld against further movement to the right with the body of the fan. Asthe fan with its motor. etc. continues to move to the right due to themomentum of such parts the control member 46 will finally pull the righthand valve suddenly into contact with the guard, at the same timesnapping the left hand valve away from the guard, whereupon thedirection of oscillation of the fan will be reversed, i. e., it will nowmove toward the left in said figure.

I .am aware that numerous efforts have been made to substitute simplerand cheaper means for the toothed gears, etc., commonly used for causingrotary fans to oscillate and I am acquainted with patents for suchdevices, but such constructions as have been suggested are usually soplaced as to interfere seriously with the airstream proceeding from thefan, and so they detract. from the efilciency of the fan. In the case ofdisks or vanes placed in front ofthe fan they also mar its appearance.and such contrivances and various others that have been suggested are ofsuch weight and construction as-to be operable only with difilcult forreversing the fan, if in fact they are operative at all to causecontinued oscillation of the fan.

It will" be obvious to those skilled in the art" that many variationsmay be made in the device herein described, all without departing frominvention,

arranged to oscillate with said fan and being so constructed as to holdone or the other of said valvemembers against the guard and the otherone away from the guard, and control means positioned. for. engagementby said connecting means. at. the end of each stroke of oscillation forreversing the relative positions of said valve members with regard tosaid guard, thereby causing the fan to oscillate. I

2. Adevice as inclaim 1,, said. valve member being. each pivotallyconnected to a. cross. member of said guard' 3. A device as in; claim'1', said valve members being each pivoted. on a. cross member? of saidguard, andsaid connecting: means being pivotally connected to the lower:ends: of said valve. members.

4. A device as in claim. 1, said: control means;

including members adjustable toward andv away from each other to varythe oscillatory: travel of said fan.

5. A device as in claim 1, said controlmeans including .a pair ofindependently movable. ele;. ments adapted to vary the travel of said:connecting means. g

6. In a fan, a rotary impeller, a skeleton guard therefore, saidimpeller and said. guard: being. mounted for movement on an axis; otherthan that of the impeller, and a closure member mountedon the peripheryof-saidzguardat: one side of the impeller to shut off the incomin airand thus to cause the. fan to rotate bodily about said axis.

7. In afan, .abase, an impeller, a guard for I being so; constructedand: arranged'as' to shu't' 01f the air passing into said guard radiallyor said impeller and thus. to cause movement of sai fan about said otheraxis.

8. A valve. for. a rotary fan havinga cylindrical guard. about the endsof its blades, said valve comprising an- 'arcuate strip of metal havig.-

means. at one end for securing it to said; 'fa-nguard so thatit li'esagainst the periphery of said guard. t i

9. A valve for a rotary fa-nha-ving a periph eral guard, said valvecom-prising an renas strip of metal having means at each end for--securing it 'tosaid fan guard so against" the periphery of said guard.

that it lies 7 10. A valve structure for a fan guardqcom prising a pairof oppositely bowed strips ef: sheet material; and a connectorsecured-to onefend of each of'said strips, said connector having:aprojecting lug midwaybetween said strips; f v

11-; combination with a bas'e; a rotary tan mounted for oscillation "onsaid base; an openwork guard for the fan, valve members on said guard atopposite sides of the fan adapted to prevent entrance of air into saidguard, and control means for said valves constructed and arranged forpositionin said valves alternately closer to the center of rotation ofthe fan, thereby causing the fan to oscillate on its base.

12. A device as in claim 11, said control means being adjustable to varythe extent of oscillation of the fan.

13. A device as in claim 11, said control means beign operable toprevent oscillation of said fan.

14. In a fan, a rotary impeller having radially extending blades, asupport therefor mounted for oscillation about an axis other than thatof the impeller, said support including portions 10- cated laterallybeyond said impeller blades, valves supported on said portions radiallyoutward beyond the ends of the fan blades for movement toward and fromthe axis of said impeller, said valves being constructed and arranged toshut off the air passing radially to said impeller, and control meansfor moving said valves thereby causing the fan to oscillate.

15. An electric fan comprising a rotary support, a motor thereon, ashaft driven by the motor, a fan on said shaft, and a guard surroundingsaid fan, means located radially outward laterally of the guard forshutting off air from one side of said fan.

JAMES D. CROOK.

